Hey mate sorry bout the lateness, ive been out of town. The haksaw cuts in the rollers are probably about 2-4mm deep. I made the cuts as rough as possible so there are lots of jagged edges to pull the grain through.

To motorize it I just made a bit the fits into a battery powered drill, it takes me about 30 mins to do a 6kg batch but I can set it up and let it run while getting other bits and pieces ready.